There are many software authorization schemes in place today. A common approach is to provide authorized users a key code to decrypt software. They key may be provided over the Internet, with product purchase or embedded in hardware. However, once a piece of software is accessible, its content is more susceptible to disassembly or decompiling.
One way of limiting disassembly or decompiling, is to limit use of disassemblers or decompilers to authorized users only. Thus, a disassembler or decompiler program would prompt a user for entry of a key to allow disassembly or decompiling to take place. Additionally, with respect to protecting software after disassembly or decompiling, others have made code difficult to follow by not having processing flow indicated by ordering of instructions. Still others have time limits processing for instructions to mitigate against step-by-step execution of instructions for those attempting to reverse engineer.
However, each of the above approaches has its own weaknesses, and thus software is routinely reversed engineered today. Accordingly, it would be desirable to make software code more difficult to reverse engineer. Furthermore, it would be desirable to provide means to make code more difficult to reverse engineer that may be used in conjunction with one or more of the above-described prior approaches.